are insufficient for Oracle, you will experience problems during installation and/or instance startup.

To modify kernel parameters a common way is to change /proc file system:

1. Log in as root user.

2. Change to the /proc/sys/kernel directory.

3. echo <desired list of values> > <group of parameters>

But this update is not permanent and after system reboot, your kernel parameters’s values will be the same as before.

A way to set kernel parameter modifications permanently, on Linux, is to includethem in a shell script. This could be run as root user, or in an automatic way at startup process (this is valid for RedHat Advanced Server and UnitedLinux)

- Create file /etc/init.d/set_kernel_parameters

#!/bin/sh

#

#

echo -n $”Start Setting kernel parameters on ”

echo 100 1024 100 100 > /proc/sys/kernel/sem

echo 2147483648 > /proc/sys/kernel/shmmax

echo 4096 > /proc/sys/kernel/shmmni

echo 2097152 > /proc/sys/kernel/shmall

echo 65536 > /proc/sys/fs/file-max

ulimit -n 65536 >/dev/null 2>&1

echo 1024 65000 > /proc/sys/net/ipv4/ip_local_port_range

ulimit -u 16384 >/dev/null 2>&1

echo -n $”End Setting kernel parameters on ”

echo

- grant execute rights on this file

$ chmod 755 /etc/init.d/set_kernel_parameters

- create symbolic link to run at startup

$ ln -s /etc/init.d/set_kernel_parameters /etc/rc.d/rc5.d/S55kernel

$ ln -s /etc/init.d/set_kernel_parameters /etc/rc.d/rc3.d/S55kernel

- make the kernel parameters active by running as root

$ /etc/init.d/set_kernel_parameters

RedHat Linux Advanced Server

——————————————

Another way to setup permanently kernel parameter values on Red Hat Advanced Server is to use ‘/etc/sysctl.conf’ file.

Every time the system boots, the ‘/etc/rc.d/rc.sysinit’ script is executed by init process. This shell script contains a call to sysctl command and

reads the values from /etc/sysctl.conf file as the ones to be set Therefore, any values added to /etc/sysctl.conf will take effect after the system boot.

sysctl.conf is a simple file containing sysctl values to be read in and set by sysctl (see man 8 sysctl).

The syntax is simply as follows:

# comment

; comment

token = value

Note that blank lines are ignored, and whitespace before and after a token

or value is ignored, although a value can contain whitespace within. Lines

which begin with a # or ; are considered remarks / comments and ignored.